This page is for the outage planner or maintenance engineer at a power station who needs temporary compressed air: for the outage crews, or to keep instrument air on while the station compressors are worked on.
JUZAIR provides power plant air compressor rental in Singapore. JUZEV electric units deliver up to 851 cfm each, per manufacturer specification, and run on the 3-phase supply a station already has. Our rental fleet is electric. Tell us where the supply point is, and we run the air to the work from there. Delivery, installation, scheduled maintenance and 24/7 support are part of the hire. For the machines themselves, see electric air compressor rental.
Where temporary air is used in a power station
- Outage tool air. Bolting, grinding and cleaning tools for turbine, boiler and heat exchanger work. The station air system is sized for normal running, not for an outage crew.
- Blasting and coating. Ducting, stacks, tanks and structures. High flow, often at higher pressure, and dry air.
- Instrument and service air cover. The rental unit carries the header while a station compressor is serviced, overhauled or replaced.
- Commissioning and testing. Air for new or repaired systems before they are handed back.
- Balance of plant. Water treatment and other auxiliary plant that needs air while its own supply is isolated.
Why an electric unit suits a power station
The power is already there. JUZEV units need 400 V, 3-phase, 50 Hz. Tell us which board or supply point you can spare during the outage and what it is rated for.
No fuel on site. There is no fuel tank beside the unit, no refuelling run during the outage and no engine exhaust.
It can stand close to the work. With no exhaust, the unit can stand in or beside a building, as long as it has fresh air in and a path for hot air to leave.
Noise is stated. 69, 72 and 75 dB(A) at full load for the three models, per manufacturer specification. The brochure does not give the measuring distance, so check the figure against your own limit.
Two limits to plan for:
- Classified areas. Parts of a power station are classified areas, for example around fuel gas and hydrogen systems. JUZEV units are not Ex-rated. They stand in an unclassified area and the air is piped to the work. Your site HSE team decides the position.
- Supply during the outage. If the board you planned to use is itself isolated for the outage, the unit needs another supply point. Our rental fleet is electric. Check this against the isolation schedule early.
Instrument air backup while station compressors are down
This is the hire where a mistake costs the most, because the plant depends on the header pressure. Give us these five things:
- Header pressure. JUZEV units are set to 7.5, 8.5, 10.5 or 13 bar(g).
- Flow. The demand the unit has to carry. The nameplate of the compressor coming out is the simplest input.
- Air quality. ISO 8573-1 sets the classes. A refrigerant dryer reaches a pressure dew point of about +3 °C (Class 4). A desiccant dryer reaches minus 40 °C (Class 2). Your station standard states the class. If your own dryers stay in service, the rental unit feeds them.
- Oil. JUZEV units are oil-flooded screw compressors with oil carry-over below 3 ppm by weight, per manufacturer specification. A lower limit needs coalescing and activated carbon filters after the compressor.
- Tie-in point. Where the unit connects, and the size of the connection. JUZEV outlets are R2″ on the JUZEV-75 and DN80 on the JUZEV-90 and JUZEV-132W.
For critical headers, ask for two units. Units can be paralleled, so one carries the load and the second stands by.
Dryers and filters can be hired together with the compressor, or bought. JUZAIR supplies refrigerant and desiccant dryers, air receivers and filtration.
Turbine outage compressed air: sizing
Size on the tools that run at the same time and on the pressure at the tool. Then decide whether one unit or two gives you the cover you want.
| At 7.5 bar(g) | At 13 bar(g) | |
|---|---|---|
| JUZEV-75 | 502 cfm | 326 cfm |
| JUZEV-90 | 587 cfm | 416 cfm |
| JUZEV-132W | 851 cfm | 587 cfm |
| Two JUZEV-90 in parallel | 1,174 cfm | 832 cfm |
| Two JUZEV-132W in parallel | 1,702 cfm | 1,174 cfm |
Maximum free air delivery at 50 Hz, per manufacturer specification. Paired figures are the two units added together. Specifications may change without notice, and model availability varies. Contact us to confirm the unit and its figures before you plan around them.
Two smaller units in place of one large one cost more floor space, but one keeps running if the other stops. On an outage with a fixed return-to-service date, that is often the better choice.
JUZEV units are variable speed. Demand swings between day and night shift, and the unit slows down when demand drops. For the step-by-step method, see the air compressor selection guide.
Planning the hire around the outage window
Before the outage. Send us the dates, the position, the supply point and the access rules. We assess the site and its electrical capacity before deployment. The units are towable and weigh 1,400 kg, 1,790 kg and 2,415 kg, for your lifting and floor loading checks.
Delivery. Tell us the delivery window, the gate passes and the inductions the crew needs. Have the unit on site and tested before the window opens, not on the first day.
During the outage. 24/7 technical and onsite support, including weekends and public holidays. Scheduled maintenance of the rental unit is part of the hire.
If the outage runs over. Tell us as soon as you know. We confirm availability for the extra time.
Other work we take on during an outage
- Station compressors. Servicing, troubleshooting and complete overhauls, including oil-free units. See air compressor repair and servicing.
- Air receivers. Hydrostatic testing and thickness gauging, with the examination documentation. MOM requires an examination by an Authorised Examiner every 2 years and a hydrostatic test at least every 10 years.
- Technicians. Turnaround manpower for shutdown work, on a project basis.
We do the same work for process plants: see petrochemical air compressor rental.
Questions from station teams
Can the compressor stand inside the turbine hall?
It has no exhaust, so a position inside a building is possible. It needs ventilation, and it must stand outside any classified area. Your site HSE team decides.
The board we would use is isolated during the outage. What then?
Tell us early. Our rental fleet is electric. The unit needs another supply point, so we place it where power is available and pipe the air to the work.
Can you hold instrument air while both station compressors are overhauled?
Yes. Tell us the header pressure, the flow and the air quality class. For a critical header we recommend two units, one running and one on standby.
Can the hire start before the outage and end after it?
Yes. We offer short-term, long-term and emergency hire. Take the unit early enough to test it on the header before the window opens, and keep it until your own compressors are back and proven under load.
Send us your outage dates
WhatsApp the dates, the flow and the pressure: +65 9631 0884.
Call the 24/7 hotline: +65 9663 6095.
Or send the details through the contact form.
